Objectives To assess the prognostic value of global magnetic resonance (MR) myocardial perfusion imaging (MPI) in women with suspected myocardial ischemia and no obstructive (stenosis <50%) coronary artery disease (CAD). Background The prognostic value of global MR-MPI in women without obstructive CAD remains unknown. Methods Women (n=100, mean age 57±11 years, range 31–76), with symptoms of myocardial ischemia and with no obstructive CAD as assessed by coronary angiography, underwent MR-MPI and standard functional assessment. During follow-up (34±16 months), time to first adverse event (death, myocardial infarction or hospitalization for worsening anginal symptoms) was analyzed using global MPI and left ventricular ejection fraction (EF) data. Results Adverse events occurred in 23 (23%). By univariable Cox proportional hazards regression modeling, variables found to be predictive of adverse events were global MR-MPI average uptake slope (p<0.05), the ratio of MR-MPI peak signal amplitude to uptake slope (p<0.05), and ejection fraction (EF) (p<0.05). Two multivariable Cox models were formed, one using variables that are performance-site dependent: ratio of MR-MPI peak amplitude to uptake slope together with EF (Chi-squared 13, p<0.005), and a model using variables that are performance-site independent: MR-MPI slope and EF (Chi-squared 12, p<0.005). Each of the two multivariable models remained predictive of adverse events after adjustment for age, disease history and Framingham risk score. For each of the Cox models, patients were categorized as high-risk if they were in the upper quartile of the model and not high-risk otherwise. Kaplan-Meier analysis of time to event was performed for high-risk vs. not high-risk for site-dependent (log rank 15.2, p<0.001) and site-independent (log rank 13.0, p<001) models. Conclusions Among women with suspected myocardial ischemia and no obstructive CAD, MR-MPI determined global measurements of normalized uptake slope and peak signal uptake, together with global functional assessment of EF appear to predict prognosis.

Myocardial flow reserve (MFR) is not routinely assessed in myocardial perfusion imaging (MPI) studies but has been hypothesized to affect test accuracy when assessing disease severity by coronary vessel lumenography. Magnetic resonance imaging (MRI) is an emerging diagnostic technique that can both perform MPI and assess MFR. We studied women (n = 184) enrolled in the Women's Ischemia Syndrome Evaluation (WISE) study with symptoms suggesting ischemic heart disease. Tests performed were coronary angiography and MPI by both MR and gated radionuclide single photon emission computed tomography (gated-SPECT). The MFR index was calculated using the MR data acquired at baseline and under vasodilation (dipyridamole) conditions. The study was structured with a pilot and an implementation phase. During the pilot phase (n = 46) data were unmasked and an MFR threshold was defined to divide patients into those with an adequate (AMFRI) or inadequate (IMFRI) MFR index. During the implementation phase, the MFR index threshold was prospectively applied to patients (n = 138). In the implementation phase, MPI ischemia detection accuracy compared to severe (> or = 70%) coronary artery diameter narrowing by angiography was higher in the AMFRI vs. the IMFRI group for MRI (86% vs. 70%, p < 0.05) and gated-SPECT (89% vs. 67%, p < 0.01). The IMFRI group (n = 55, 30% of study population) had a higher resting rate-pressure product compared with the AMFRI group (10,599 +/- 2871 vs. 9378 +/- 2447 bpm mm Hg, p < 0.01), consistent with higher resting myocardial flow. When compared with each other, MRI and gated-SPECT MPI showed no difference in accuracy among MFR groups. Myocardial perfusion patterns in the IMFRI group may have resulted in atypical perfusion patterns, which either masked or mimicked epicardial coronary artery disease.

This proof-of-principle study demonstrates that reversible RV perfusion defects suggestive of ischemia can be detected by SPECT myocardial perfusion imaging in some patients with LV inferior ischemia by visual analysis and can be quantitated by automated programs. Further studies on the diagnostic and prognostic relevance of assessing RV ischemia on SPECT MPI are needed.

TID on regadenoson MPI carries important prognostic information that is independent from PDS and LVEF, but this association is restricted to patients with abnormal perfusion on imaging.

Background:We introduce an algorithmic approach to optimize diagnostic and prognostic value of gated cardiac single photon emission computed tomography (SPECT) and magnetic resonance (MR) myocardial perfusion imaging (MPI) modalities in women with suspected myocardial ischemia. The novel approach: bioinformatics assessment schema (BIAS) forms a mathematical model utilizing MPI data and cardiac metrics generated by one modality to predict the MPI status of another modality. The model identifies cardiac features that either enhance or mask the image-based evidence of ischemia. For each patient, the BIAS model value is used to set an appropriate threshold for the detection of ischemia.Methods: Women (n=130), with symptoms and signs of suspected myocardial ischemia, underwent MPI assessment for regional perfusion defects using two different modalities: gated SPECT and MR. To determine perfusion status, MR data were evaluated qualitatively (MRI QL ) and semi-quantitatively (MRI SQ ) while SPECT data were evaluated using conventional clinical criteria. Evaluators were masked to results of the alternate modality. These MPI status readings were designated "original". Two regression models designated "BIAS" models were generated to model MPI status obtained with one modality (e.g., MRI) compared with a second modality (e.g., SPECT), but importantly, the BIAS models did not include the primary Original MPI reading of the predicting modality. Instead, the BIAS models included auxiliary measurements like left ventricular chamber volumes and myocardial wall thickness. For each modality, the BIAS model was used to set a progressive threshold for interpretation of MPI status. Women were then followed for 38±14 months for the development of a first major adverse cardiovascular event [MACE:CV death, nonfatal myocardial infarction (MI) or hospitalization for heart failure]. Original and BIASaugmented perfusion status were compared in their ability to detect coronary artery disease (CAD) and for prediction of MACE.Results: Adverse events occurred in 14 (11%) women and CAD was present in 13 (10%). There was a positive correlation of maximum coronary artery stenosis and BIAS score for MRI and SPECT (P<0.001).Receiver operator characteristic (ROC) analysis was conducted and showed an increase in the area IntroductionPreviously we showed that the initial (i.e., "original") interpretation of myocardial perfusion imaging (MPI) was improved by modeling the results of one modality, such as magnetic resonance imaging (MRI), against the results of another modality, such as single photon emission computed tomography (SPECT) for diagnosis and prognosis in women with signs and symptoms of ischemia (1). This approach, termed Decisions Informed by Combining Entities (DICE) better identified women likely to experience a major adverse cardiovascular event (MACE) versus the original reading. However, since the DICE formula incorporated the Original MPI reading it was constrained to convert false negatives to true positives, but did not convert fal...